In 2005 Mercedes-Benz come with an idea of launching an SUV based on the Smart platform.
Now, the German carmaker is bringing back to life those plans and according to German magazine Auto Motor and Sport in 2016 we will see an SUV build by Smart. The concept unveiled in 2005 was called Smart ForMore, but it never got to see the day light. 

The Smart SUV will have an increased ride high, a new massive body work and a four wheel drive system. According to the same source, the SUV will be built on the platform of the second generation of the ForTwo. 

Speaking of 2nd gen Smart ForTwo, it will be unveiled later this year, and will go on sale in 2014.

Source: WCF